Researchers from Cambridge University announced the shocking discovery of the wax moth larvae’s ability to eat away plastic.
These caterpillars usually feed themselves with bee wax, but it appears that they can degrade plastic with the same ease, making holes in plastic bags in less than an hour.
Researchers assure that this is just “the starting point” and that future efforts may allow minimizing the impact of plastic waste on a global scale.
Finally, plastic is degradable!
The initial find was by Federica Bertocchini from the Institute of Biomedicine and Biotechnology of Cantabria, Spain, as she put some Galleria mellonella larvae in a plastic bag. Hours later, she realized that the bag had holes all over it. It turns out that the larvae of the wax moth can degrade polyethylene into ethylene glycol.
Polyethylene or plastic has been known for its resistance to degradation, especially to biodegradation, although previous studies have managed to degrade it within a set of specific conditions. Scientists managed to degrade plastic by incubating a piece of polyethylene with the fungus Penicillium simplicissimum for three months after treating the sample with nitric acid. They were also able to degrade plastic by using the bacteria Nocardia asteroids, although in both cases, the process was slow and tedious.
Now, when a polyethylene film was left in direct contact with wax worms, in just 40 minutes, the worms had already made some holes in it. The team established a 2.2 to 1.2 holes per worm per hour ratio.
In the study, they tested putting about 100 worms in contact with a plastic shopping bag for 12 hours. This resulted in a loss of 92 mg of material, or 13 percent of the sample’s polyethylene content, being a faster process in plastic degradation than any other.
“We are planning to implement this finding into a viable way to get rid of plastic waste, working towards a solution to save our oceans, rivers, and all the environment from the unavoidable consequences of plastic accumulation,” stated Dr. Bertocchini.
Apparently, the most common hydrocarbon bond in beeswax is CH2-CH2, just as in polyethylene. Researchers theorize that the C-C single bond of these compounds is one of the primary targets of the larva’s digestive process. When analyzed using Fourier Transform Infrared Spectroscopy or FTIR, indicators of the breakdown of polyethylene were observed.
They are not sure whether the “hydrocarbon-digesting activity” of Galleria mellonella is produced by the larva itself or from the enzymes in its intestinal flora.
Although the biodegradation of polyethylene may now be a reality, Dr. Bertocchini urges the public to keep refraining from deliberately dumping plastic in the environment.
According to UC Santa Barbara’s National Center for Ecological Analysis and Synthesis, every year, 8 million metric tons of plastic end up in the ocean. This is equivalent to five grocery bags full of plastic for every foot of coastline. If left without constraint, by 2025 there will be about 20 times the amount there is today. Furthermore, plastic kills about 100,000 marine mammals each year, without taking into account birds and fishes.
Source: Cell